Fig. 1. Picture of laser induced breakdown spectrometer

Fig. 2. Pictures of representative rock tablet samples

Fig. 3. Schematic diagram of data analysis process

Fig. 4. LIBS spectrum of representative rock samples（GBW07111）

Fig. 5. Comparison of the calibration curves of five elements based on the original peak intensity and three different pretreatment methods

Fig. 6. Ideal and actual peak intensities

Fig. 7. Cumulative interpretation rates of PCs based on two different pretreatment methods

Fig. 8. Quantitative models of Si，Mg，Al and K

Fig. 8. Predictive performance of quantitative analysis for the five target elements on test data

Fig. 10. Predictive performance of quantitative analysis for the five target elements of samples of cuttings

Fig. 11. The content change curves of five elements in the samples of cuttings